296 GEOGRAPHICAL AND GEOLOGICAL DISTRIBUTION. 



six genera (Gadus, Merlucius, Lotella, Motella, &c.) in the fauna of 

 New Zealand. The Chilian fauna is generically closely related to 

 the South Australian, and contains but few types that are strictly 

 peculiar to it. One of its more remarkable features is the posses- 

 sion of a species of Polyprion (P. Kneri, from Juan Fernandez), 

 one of the Percidae, the only other known species of the genus (P. 

 cernium) being a member of the European fauna.* The number of 

 fishes thus far obtained from the Patagonian province is very 

 limited, and scarcely permits us to formulate any definite opinion 

 as to the characters of the entire fauna. 



The equatorial shore fishes far exceed those of the temperate 

 zones both in number and diversity of form, agreeing in this re- 

 spect with the condition presented by equatorial land and fluviatile 

 faunas generally. It is here, too, that we find grotesqueness of 

 outline combined with a most varied and beautiful colouring, an 

 almost infinite arrangement of lively tints, scarlet, yellow, blue, 

 black, &c., imparting to the fishes of this tract an indescribable 

 brilliancy. Throughout the greater part of the equatorial or tropi- 

 cal belt there is manifest a strong faunal identity, rendering the 

 institution of ichthyic provinces practically impossible. Thus, the 

 greater number of the dominant types of the Atlantic Ocean are 

 also represented in the Pacific, and vice versa, and in many instances 

 even the species representing these types are identical. The fishes 

 of the tropical waters of the Indian and Pacific oceans are very 

 intimately related, the number of identical species ranging from 

 the Red Sea far into the Polynesian Archipelago being very great. 

 A limit to the eastward extension of the Indo-Pacific fauna appears 

 to have been set, however, by the cold current sweeping northward 

 along the western coast of South America, aqd as a consequence we 

 find a more or less distinct, or individualised, fauna along the east- 

 ern border of the great ocean. Among the more largely represented 

 generic or family groups of the equatorial zone are the sea-perches 

 (Serranus), snappers (Mesoprion), mullet-kings (Apogon), blow- 

 fishes (Chaetodon, &c.), Scorpaenidae, horse-mackerels (Caranx), 

 coral-fishes (Pomacentridse), Julidinae, flat-fishes (Pleuronectidae), 

 herrings, and Mursenidae, several of which are more or less distinc- 

 tive of the zone. In all of these groups the number of species in 



* Obtained also in deep water by the United States Fish Commission. 

 (Jordan and Gilbert, " Synopsis Fishes of North America," 18S2.) 



